inst and extdata folders in R Packaging

Question

In the documentation, R suggests that raw data files (not Rdata nor Rda) should be placed in inst/extdata/

From the first paragraph in: http://cran.r-pr

Answer 1

You were both very close and essentially had this. A formal reference from 'Writing R Extensions' is:

1.1.3 Package subdirectories

[...]

The contents of the inst subdirectory will be copied recursively to the installation directory. Subdirectories of inst should not interfere with those used by R (currently, R, data, demo, exec, libs, man, help, html and Meta, and earlier versions used latex, R-ex). The copying of the inst happens after src is built so its Makefile can create files to be installed. Prior to R 2.12.2, the files were installed on POSIX platforms with the permissions in the package sources, so care should be taken to ensure these are not too restrictive: R CMD build will make suitable adjustments. To exclude files from being installed, one can specify a list of exclude patterns in file .Rinstignore in the top-level source directory. These patterns should be Perl-like regular expressions (see the help for regexp in R for the precise details), one per line, to be matched(10) against the file and directory paths, e.g. doc/.*[.]png$ will exclude all PNG files in inst/doc based on the (lower-case) extension.

Answer 2

More useful than using file.path would be to use system.file. Once your package is installed, you can grab your file like so:

fpath <- system.file("extdata", "my_raw_data.csv", package="my_package")

fpath will now have the absolute path on your HD to the file.